I did not want to continue fueling the hi-jacking of the "better tasting semen" thread with this post, and instead thought it would be helpful to have this put into perpetuity in a central location to stand alone for folks that want medical facts whenever this hot issues rises, which seems to be every few weeks.
Here is what the CDC has to say about the BBBJ:
Not having sex is the best way to protect against the transmission of HIV.
But if you are having sex, it’s important to know that all sex is not the same when it comes to transmitting HIV. For instance insertive oral sex without a condom has a low risk for HIV transmission (about 1 in 4,000) and in each of these cases the transmission actually occurred as a direct result of open sores and cuts on either the penis or the mouth of one of the partners. It should also be noted that in each of these cases other unprotected sexual activity was conducted. There are no known cases of HIV as the result of strictly orogenital contact. While some studies have shown a very low level of infected cells can be present in both semen and pre-ejaculate fluid, the virus does not live long outside the body and saliva has indeed shown the ability to inhibit if not kill the virus. Saliva that does not contain blood presents no potential for transmission, as research has shown that an enzyme in saliva inhibits HIV. In general, the mouth and throat are well defended against HIV: the oral mucosal lining contains few of the cells that are the most susceptible to HIV.28 Other research notes that saliva contains several HIV inhibitors, such as peroxidases and thrombospondin-1, and that the hypotonicity of saliva disrupts the transmission of infected leukocytes (white blood cells).
Recent studies indicate that the population-attributable risk percentage (PAR%) for HIV prevalence associated with fellatio while using a condom is 0.18% and without a condom 0.14% if that is the only sexual activity that is unprotected.
References:
1. Centers for Disease Control and Prevention. Incorporating HIV Prevention into the Medical Care of Persons Living with HIV:
Recommendations of CDC, the Health Resources and Services Administration, the National Institutes of Health, and the HIV
Medicine Association of the Infectious Diseases Society of America. MMWR 2003;52(RR-12):1–24.
2. Varghese B, Maher JE, Peterman TA, Branson, BM, Steketee RW. Reducing the risk of sexual HIV transmission: quantifying the
per-act risk for HIV infection based on choice of partner, sex act, and condom use. Sexually Transmitted Diseases 2002;29:38–43.
3. Centers for Disease Control and Prevention. HIV/AIDS Questions and Answers. Available at: www.cdc.gov.
4. Centers for Disease Control and Prevention. HIV testing among pregnant women—United States and Canada, 1998-2001.
MMWR 2002;51(45):1013–1016.
5. Dorenbaum A, Cunningham CK, Gelber RD, et al. Two-dose intrapartum/newborn nevirapine and standard antiretroviral
therapy to reduce perinatal HIV transmission: a randomized trial. Journal of the American Medical Association 2002;288:189–198.
6. Centers for Disease Control and Prevention. Is there a connection between HIV and other sexually transmitted diseases? Available at www.cdc.gov